CN106028811A - Biocidic microcapsules - Google Patents

Abstract

The present invention relates to microcapsules which contain one or more biocides such as in particular iodopropargyl compounds and at least one melamine-formaldehyde polymer, a method for the production of said microcapsules, and the use thereof for protecting technical materials.

Description

biocidal microcapsules

The present invention relates to microcapsules comprising one or more biocides such as in particular iodopropargyl compounds and at least one melamine-formaldehyde polymer, and to a process for the production of such microcapsules, and to Its use for the protection of industrial materials.

Iodopropargyl compounds are especially used in material protection for the protection of industrial materials such as adhesives, sizes, paper and cardboard, textiles, leather, wood, wood-based materials, paints and plastics, cooling lubricants and possibly Known active ingredients that protect other materials from attack or breakdown by microorganisms, in particular by fungi. The most famous representative of iodopropargyl compounds is iodopropargyl butylcarbamate, also referred to hereinafter as IPBC.

High demands are placed on fungicides for the finishing of coating compositions such as, for example, wood protection paints, exterior paints or plasters. For example, fungicidally finished coating compositions must remain stable even in frequent contact with water and must not undergo any unwanted discoloration. Since some fungicides, like IPBC for example, are somewhat water soluble, the fungicide is washed off from exterior paints as a result of eg contact with heavy rain. This process is also known as "leaching". This leads to a reduction of the fungitoxic effect in these coating compositions and to a serious local burden of these active ingredients or their metabolites on the environment. The leaching should be low in order to protect the coating compositions as well as the exterior walls against fungal attack over a long period of time. One option to reduce leaching is to use microencapsulation.

Coating compositions protected against attack by microorganisms and methods for producing microencapsulated biocides are known from the prior art.

Thus, for example, WO 04/000953 A1 describes a coating composition for protecting surfaces from microorganisms by subjecting the surface to the action of moisture or water, wherein the coating composition either itself has a pH of at least 11.0 or is Intended for coating matrix materials whose pH is at least 11.0. The coating composition is characterized in that it contains a biocide, like for example IPBC, which is bound to a carrier material made of solid particles and is thus released in a delayed manner.

DE 102006061890 A1 describes sealing compositions comprising, for example, 2-n-octyl-4-isothiazolin-3-one as biocide and optionally one or more further biocides, wherein the biocide Enclosed in microcapsules made, for example, of aminoplast resins.

It is known from DE 10133545 A1 to treat sealing compositions with specific benzothiophene fungicide preparations in order to prevent the polymer mass from becoming moldy. Reference is also made here to the difficulty of finding suitable fungicides for sealing compositions which are stable and do not undergo wash-off. Therefore, the pesticides used must be used in high concentrations, which also has the potential to cause environmental impacts.

It is known from JP 2002-053412 A2 that biocides can be enclosed in a resin matrix. Thus, the inclusion of 2-n-octyl-4-isothiazolin-3-one in a styrene-maleic anhydride resin is described in this document.

EP 0 758 633 A1 describes porous particles which may contain chemical substances, but also eg biocides, which slowly release these substances during use.

JP 2004099557 A2 describes fine particles of biocide-containing resins for inhibiting the growth of microorganisms, especially in aqueous emulsion paints.

However, these microcapsules known from the prior art still do not have a satisfactory antifungal action combined with a simultaneously low leaching rate and high tolerance or storage stability.

It was therefore an object of the present invention to provide microcapsules which allow an improved protection of coating compositions against fungal attack.

The solution to said problem and the subject of the present invention are then microcapsules comprising at least one iodopropargyl compound, wherein the at least one iodopropargyl compound is coated with at least one melamine-formaldehyde polymer The microencapsulated material is microencapsulated.

The scope of the present invention includes all parameters and interpretations above and below, whether they are indicated in general with each other or within preferred ranges, ie or in any desired combination between these corresponding ranges and preferred ranges.

The microcapsules according to the invention comprise at least one iodopropargyl compound selected from the group consisting of:

3-iodo-2-propynylpropylcarbamate, 3-iodo-2-propynylbutylcarbamate (IPBC), 3-iodo-2-propynyl m-chlorobenzene Base carbamate, 3-iodo-2-propynyl phenyl carbamate, 3-iodo-2-propynyl 2,4,5-trichlorophenyl ether, 3-iodo- 2-propynyl 4-chlorophenyl formal (IPCF), bis-(3-iodo-2-propynyl)hexyl dicarbamate, 3-iodo-2-propynyloxyethanol Ethyl carbamate, 3-iodo-2-propynyloxyethanol phenyl carbamate, 3-iodo-2-propynylthiothio-ethyl carbamate, 3 -Iodo-2-propynylcarbamate (IPC), N-iodopropargyl-oxycarbonylalanine, N-iodopropargyloxycarbonylalanine ethyl ester, 3 -(3-iodo-propargyl)benzoxazol-2-one, 3-(3-iodopropargyl)-6-chlorobenzoxazol-2-one, 3-iodo-2 -propynyl alcohol, 4-chlorophenyl 3-iodopropargyl formal, 3-bromo-2,3-diiodo-2-propenylethylcarbamate, 3-iodo- 2-propynyl-n-hexyl carbamate, 3-iodo-2-propynyl cyclohexyl carbamate.

A particularly preferred iodopropargyl compound is 3-iodo-2-propynylbutylcarbamate (IPBC).

These iodopropargyl compounds are known per se and can be prepared by methods known in the literature or are commercially available.

Microencapsulation of these iodopropargyl compounds takes place by means of microencapsulating materials. In the context of the present invention, microencapsulation means at least partial, preferably complete covering of the at least one iodopropargyl compound with a microencapsulating material.

The microcapsules according to the invention have, for example, a volume average particle diameter of from 0.3 to 100 μm, preferably from 5 to 60 μm.

In another embodiment, the microcapsules according to the invention have a D90 value of, for example, 90 μm or less, preferably 60 μm or less, particularly preferably 10 to 60 μm (determined by laser diffraction as volume-weighted distribution as described in the experimental part of).

The microcapsules according to the invention comprise at least one melamine-formaldehyde polymer as microencapsulation material. The term melamine-formaldehyde polymer is understood to mean a polymer which is a condensation polymer of at least melamine and formaldehyde. Such polycondensates are typically obtained by polycondensation of melamine with a molar excess of formaldehyde.

General methods for the production of microcapsules, in particular also for the production of melamine-formaldehyde polycondensates, are known (see for example C.A. Finch, R. Bodmeier, Microencapsulation, Ullmann Chemical Industry Encyclopedia Complete book (Ullmann's Encyclopedia of Industrial Chemistry), 6th edition, 2001, electronic distribution).

The microcapsules according to the invention may eg comprise at least one further microencapsulating material selected from the group of synthetic, semi-synthetic or natural polymers, such as in particular aminoplast resins.

Aminoplast resins are generally understood to mean polycondensation products of carbonyl compounds and compounds containing NH groups. Of particular interest in this connection are melamine-formaldehyde resins modified with urea or phenyl groups (melamine-urea-formaldehyde resins, melamine-phenol-formaldehyde resins). As a further possible aminoplast resin, it is possible, for example, to add an aminoplast resin of a compound containing NH groups and acetaldehyde or glyoxal to the melamine-formaldehyde resin.

In addition, the microencapsulation material may comprise urethane resins, aminoamine resins or dicyandiamide resins, aniline resins, sulfonamide resins or mixtures of these resins. Such resins and their production are known to those skilled in the art.

Preferred synthetic polymers are, for example, acrylic polymers and copolymers, polyacrylamides, polyalkylcyanoacrylates, and poly(ethylene vinyl acetate), aluminum monostearate, carboxyvinyl polymers, polyamides, Poly(methyl vinyl ether-maleic anhydride), poly(adipyl-L-lysine), polycarbonate, polyterephthalamide, poly(vinyl acetate phthalate ester), poly(terephthaloyl-L-lysine), polyaryl sulfone, poly(methyl methacrylate), poly-(ε-caprolactone), polyvinylpyrrolidone, polydimethyl Silicone, polyethylene oxide, polyester, polyglycolic acid, polylactic acid and its copolymers, polyglutamic acid, polylysine, polystyrene, poly(styrene-acrylonitrile), polyimide and polyvinyl alcohol.

Preferred semi-synthetic polymers are e.g. cellulose acetate, cellulose acetate butyrate, cellulose acetate phthalate, nitrocellulose, ethyl cellulose, hydroxypropyl cellulose, sodium carboxymethyl cellulose, hydroxy Propyl Methyl Cellulose, Methyl Cellulose, Hydroxypropyl Methyl Cellulose Phthalate, Hydrogenated Beef Butter, Myristyl Alcohol, Glycerol Mono- or Di Palmitate, Hydrogenated Castor Oil, Mono - or glyceryl tristearate ethyl 12-hydroxystearate alcohol.

Preferred natural polymers are e.g. gum arabic, agar, agarose, maltodextrin, sodium alginate, calcium alginate, dextran, fats, fatty acids, cetyl alcohol, milk solids, molasses, gelatin, gluten, albumin, Shellac, starch, caseinates, stearns, sucrose, and waxes such as beeswax, carnauba wax, and spermaceti.

In general, the microencapsulated material may comprise, in addition to at least one melamine-formaldehyde polymer, up to 50% by weight, based on its total weight, of other synthetic or semi-synthetic or natural polymers, such as in particular Aminoplast resin.

Preferably, the microencapsulated material comprises at least 95% by weight of at least one melamine-formaldehyde polymer, particularly preferably at least 99% by weight of at least one melamine-formaldehyde polymer.

Generally, the weight ratio (w/w) of the microencapsulating material to the at least one iodopropargyl compound in the microcapsules according to the invention is from 1:10 to 100:1, preferably from 1:10 to 10:1 and very particularly preferably from 1:4 to 2:1.

The present invention also covers a method for producing microcapsules according to the present invention, characterized in that the method comprises at least:

a) Applying a microencapsulated material comprising at least one melamine-formaldehyde polymer to at least one iodopropargyl compound

b) during the period of t, at temperatures from 50°C to 95°C, preferably 64°C to 95°C, preferably 68°C to 95°C, particularly preferably 70°C to 95°C and very particularly preferably 70°C to 90°C °C at a temperature T such that the product T×T×t is >18000, preferably >20000 and particularly preferably >25000 (°C) ² h.

According to a), the at least one melamine-formaldehyde polymer is applied to the at least one iodopropargyl compound.

Melamine-formaldehyde polymers suitable for this are sufficiently known and are known, for example, under the trade name (BASF AG), (Ineos Melamines), (Thor GmbH) or can be produced from melamine and formaldehyde by methods known per se as described, for example, in WO 2008/000797 A2.

The application in a) is preferably carried out in such a way that the aqueous emulsion or suspension of the at least one iodopropargyl compound is mixed with at least one melamine-formaldehyde polymer (preferably dissolved in an aqueous medium) contacting, and causing application of the at least one melamine-formaldehyde polymer to the at least one iodopropargyl compound by reducing the solubility of the at least one melamine-formaldehyde polymer.

A reduction in solubility can take place here by increasing the electrolyte content, for example by adding salt or an aqueous saline solution or by adjusting the pH.

Suitable conditions for applying the polymer to the iodopropargyl compounds can be determined experimentally in some preliminary experiments without much effort. For example, the application can take place at a pH measured in the range from 0 to 6.5, preferably from 1.0 to 4.0, particularly preferably from 2.50 to 3.50 and very particularly preferably from 2.80 to 3.20 or based on standard conditions.

In the process according to the invention for producing the microcapsules according to the invention, the application of these melamine-formaldehyde polymers can take place within a wide temperature range, for example the application is from 10°C to 95°C, preferably from 50°C to 95°C, particularly preferably at a temperature in the range from 64°C to 95°C, very particularly preferably at a temperature of 68°C to 95°C, even further preferably at a temperature of 70°C to 95°C and very particularly preferably Occurs at temperatures between 70°C and 95°C. In particular, when IPBC is used, it is advantageous that the temperature is from 68°C to 95°C, preferably 70°C to 95°C and particularly preferably 70°C to 90°C, because these temperatures are at or above the upper end of the melting point range of IPBC (64°C-68°C).

Contacting and application can take place, for example, such that first the aqueous emulsion or suspension of the at least one iodopropargyl compound is introduced and an aqueous solution of at least one melamine-formaldehyde polymer is added, before which the at least one melamine-formaldehyde polymer is added. The solubility reduction of the oxymethylene polymer preferably occurs by adjusting the pH.

In this case, the addition of the electrolyte or the adjustment of the pH is for example directly or within a period of at least one minute, preferably within a period of at least 30 minutes to 24 hours, particularly preferably within a period of at least one hour and very It particularly preferably takes place over a period of at least 2 to 6 hours.

Alternatively, the contacting and application can take place, for example, so that an aqueous emulsion or suspension of the at least one iodopropargyl compound is provided, wherein conditions are established which preferably cause the at least one melamine to react by adjusting the pH. - Application of an oxymethylene polymer and then adding at least one aqueous solution of melamine-formaldehyde polymer.

To establish the pH, inorganic or organic acids can be used, such as, for example, hydrochloric acid, sulfuric acid, phosphoric acid or citric acid, oxalic acid, acetic acid, formic acid, acid salts or any desired mixtures of the aforementioned compounds.

Iodopropargyl compounds are typically only poorly soluble in water.

In a), therefore, preferably an aqueous emulsion or suspension of the iodopropargyl compound, or a solution of the iodopropargyl compound in an organic solvent is used. In this regard, it is clear to the person skilled in the art that in order to produce emulsions of iodopropargyl compounds in organic solvents it is necessary to use those organic solvents which are immiscible or at least not completely miscible with water.

In a particularly preferred embodiment, in step a), an aqueous solution of at least one iodopropargyl compound is used.

In an alternative embodiment, an aqueous emulsified melt of at least one iodopropargyl compound is used.

In a), it is also possible to add further auxiliaries known to the person skilled in the art to the aqueous emulsion or suspension, such as, for example, protective colloids.

Suitable protective colloids are for example polyacrylates, preferably BR3 (Coatex), partially saponified polyvinyl acetate, polyvinyl alcohol, polyvinylpyrrolidone, cellulose ethers (Tylose), such as, for example, methylcellulose, hydroxyethylcellulose or hydroxypropylmethylcellulose, Starch, protein, gum arabic, alginate, pectin, gelatin or mixtures of these compounds. Particular preference is given to using a mixture of gum arabic and polyacrylate as protective colloid.

The protective colloid is typically at least part of a constituent of the microencapsulated material as described above.

In the process according to the invention for producing the microcapsules according to the invention, according to b), at from 50°C to 95°C, preferably from 64°C to 95°C, preferably from 68°C to 95°C, particularly preferably at 70 °C to 95°C and very particularly preferably a treatment temperature T of 70°C to 90°C occurs within a time period t such that the product T×T×t is >18 000, preferably >20 000, for example like >20 000 to 300 000 and particularly preferably >25 000, eg like >25 000 to 300 000 (° C.) ² h. Treatment at a certain temperature is understood to mean the treatment of the microcapsules as soon as they are formed according to a), ie from the application of the microencapsulating material. The characteristic according to b) is therefore already fulfilled when the application temperature is within the abovementioned temperature interval.

The treatment according to b) may alternatively or additionally also take place by exposing the microcapsules to temperatures within the stated intervals when the application is complete. The exposure can take place, for example and preferably, by post-stirring, standing or storage of the reaction mixtures, or by storage after, for example, isolation of the microcapsules.

Without wishing to be bound by science in any way, it is assumed that any groups which have not yet been crosslinked or which have not been polymerized become crosslinked or polymerized as a result of the treatment at the aforementioned temperatures.

The treatment at the aforementioned temperatures preferably takes place within a period of one hour or more, preferably within a period of from 1 to 30 hours, particularly preferably within a period of from 5 to 30 hours.

Longer time periods no longer provide significant improvements.

In a preferred embodiment, the treatment and the above product refer to the time period and temperature after the application is complete.

In an alternative embodiment, it is possible to add urea to the suspension or emulsion of the iodopropargyl compound to produce the microcapsules according to the invention. This urea addition can eg take place before the treatment according to b). In an alternative embodiment, this urea addition can also take place directly after the treatment according to b). In a further alternative embodiment, the addition of the urea can take place after the heat treatment during formulation with further auxiliaries like for example packaging preservatives and emulsifiers. Preferably, the addition of the urea takes place after the heat treatment during the formulation with further auxiliaries.

The addition of urea can also take place during the production of formulations from these isolated microcapsules.

The amount of urea added is, for example, 0.1% to 20% by weight, preferably 1% to 10% by weight, particularly preferably 2% to 5% by weight, based on the total amount of microencapsulated material used.

The process according to the invention for producing the microcapsules according to the invention can be carried out under any desired pressure. Preferably, the process according to the invention for producing the microcapsules according to the invention is carried out at atmospheric pressure.

The microcapsules according to the invention can then be isolated, eg by filtration, settling or centrifugation, and optionally dried at room temperature or by gentle heat. However, there is also the option of drying and isolating these microencapsulated materials by spray drying or freeze drying. Preferably, the microcapsules according to the invention are isolated by filtration and used without further drying for the production of formulations.

The microcapsules which can be produced according to the invention surprisingly have a reduced leaching rate compared to other microencapsulation methods and are therefore particularly advantageous.

Accordingly, the present invention further comprises microcapsules obtainable by the process according to the invention and/or microcapsules comprising at least one iodopropargyl compound, wherein the at least one iodopropargyl compound is treated with at least one melamine - oxymethylene polymer microencapsulation and wherein these microcapsules have 1 to 80 ppm (unless stated otherwise, ppm always refers to ppm by weight), preferably from 2 to 50 ppm, particularly preferably from 5 to 40 ppm and very particularly preferably 5 The 24h leaching rate as determined by means of the 24h leaching test as given in the examples to 30 ppm.

The microcapsules according to the invention are particularly suitable for or as biocides, in particular fungicides. Accordingly, the present invention also includes biocides comprising microcapsules according to the invention, and the use of microcapsules according to the invention as or in biocides.

The microcapsules according to the invention are characterized by high potency and their broad spectrum of activity against fungi.

By way of example, microorganisms of the following genera may be mentioned:

Alternaria, such as Alternaria,

Aspergillus, such as Aspergillus niger,

Chaetomium, such as Chaetomium globosa,

Pyrocystium spp., such as Pyrocystium simplex,

Shiitake mushrooms, such as tiger skin shiitake mushrooms,

Penicillium, such as Penicillium cinerea,

Polyporus, such as versicolor versicolor,

Aureobasidium, such as Aureobasidium pullulans,

Sclerophoma, such as Sclerophoma pityophila,

Trichoderma, such as Trichoderma viride.

The biocides according to the invention can be present in any desired formulations, for example in the form of suspension concentrates, water-dispersible powders, water-dispersible granules or simple powder mixtures, preference being given to suspensions Concentrates, powder mixes and water dispersible granules.

In principle, the preferred type of formulation depends essentially on the intended use and the physical properties required for that use. However, since these are known, it is routine for a person skilled in the art to determine the preferred type of formulation in several experiments.

These formulations may also contain additional substances such as stabilizers, packaging preservatives and additional biocides such as, for example, fungicides, algicides, insecticides, acaricides, nematicides, radiation sterilization and herbicides or mixtures thereof, preferably fungicides or algicides, or mixtures thereof, very preferably algicides, in each case independently of each other in microencapsulated form or non-microencapsulated Encapsulated form.

In addition to the microcapsules according to the invention, these biocides may optionally further comprise various adjuvants. For the auxiliaries indicated below, there is also the option of their absence in each case independently of one another. Possible auxiliaries are, for example:

· Surface-active substances, like for example surfactants. Surfactants may be, for example, nonionic, cationic and amphoteric surfactants, preferably anionic surfactants. Anionic surfactants are, for example, alkyl sulfates, alkyl ether sulfates, alkylarylsulfonates, alkylsuccinates, alkylsulfosuccinates, N-alkoxysarcosinates, acyl Taurates, acyl isethionates, alkyl phosphates, alkyl ether phosphates, alkyl ether carboxylates, alpha-olefin sulfonates, in particular alkali metal salts and alkaline earth metal salts, such as , sodium, potassium, magnesium, calcium and also ammonium and triethanolamine salts. These alkyl ether sulfates, alkyl ether phosphates and alkyl ether carboxylates may have, for example, from 1 to 10 ethylene oxide or propylene oxide units, preferably 1 to 3 oxirane units, in each case. ethane unit. For example, sodium lauryl sulfate, ammonium lauryl sulfate, sodium lauryl ether sulfate, ammonium lauryl ether sulfate, sodium lauryl sarcosinate, sodium oleyl succinate, ammonium lauryl sulfosuccinate, dodecylbenzene Sodium sulfonate, triethanolamine dodecylbenzenesulfonate are suitable. The biocide according to the invention may comprise here, for example, from 0.01% to 10% by weight, preferably from 0.2% to 8% by weight, particularly preferably from 0.3% to 5% by weight, and very particularly preferably by From 0.5% to 3% by weight of surface-active substances.

· Defoamer. The defoamer used is generally a surface-active substance that is hardly soluble in the surface-active solution. Preferred antifoam agents are those derived from natural fats and oils, petroleum derivatives, or silicone oils.

Wetting agents such as, for example, alkali metal salts, alkaline earth metal salts, ammonium salts of the following acids: aromatic sulfonic acids, such as lignin-, phenol-, naphthalene- and dibutylnaphthalenesulfonic acids; and also fatty acids , alkyl- and alkylaryl sulfonates, alkyl, lauryl ether and fatty alcohol sulfates; and sulfated salts of hexyl-, heptyl- and stearyl alcohol or fatty alcohol glycol ethers, Polycondensation products of sulfonated naphthalene and its derivatives with formaldehyde, polycondensation products of naphthalene or polycondensation products of naphthalenesulfonic acid with phenol and formaldehyde, polyoxyethylene octylphenol ether, ethoxylated isooctylphenol, octylphenol or nonylphenol, alkylphenol or tributylphenyl polyglycol ether, tristearylphenyl ether ethoxylate, alkylaryl polyether alcohol, isotridecyl alcohol, aliphatic alcohol ring Ethylene oxide polycondensates, ethoxylated castor oil, polyoxyethylene alkyl ethers and polyoxypropylenes, lauryl alcohol polyglycol ether acetate, sorbitan esters, lignin sulfite waste or Methylcellulose. The biocide according to the invention may comprise here, for example, from 0.01% to 8% by weight, preferably from 0.2% to 6% by weight, particularly preferably from 0.3% to 5% by weight, and very particularly preferably by From 0.5% to 3% by weight of wetting agent.

• Emulsifiers such as, for example, sodium, potassium and ammonium salts of linear aliphatic carboxylic acids of chain length C ₁₀ -C ₂₀ . Sodium hydroxyoctadecanesulfonate, sodium, potassium and ammonium salts of hydroxy fatty acids with a chain length of C ₁₀ -C ₂₀ and their sulfurized or acetylated products, alkyl sulfates, such as triethanolamine salts, alkyl-(C ₁₀ -C ₂₀ )-sulfonate, alkyl-(C ₁₀ -C ₂₀ )-arylsulfonate, dimethyldialkyl-(C ₈ -C ₁₈ )-ammonium chloride, acyl, alkyl, Oleyl and alkaryl ethoxylates and their vulcanized products, alkali metal salts of sulfosuccinates with aliphatic saturated monohydric alcohols with a chain length of C ₄ -C ₁₆ , with monoalcohols with a chain length of C ₁₀ -C ₁₂ 4-Sulfosuccinate (disodium salt) of polyethylene glycol ethers of hydroxyaliphatic alcohols, 4-sulfosuccinate (disodium salt) of polyethylene glycol nonylphenyl ethers, sulfosuccinate Acid bis-cyclohexyl ester (sodium salt), lignosulfonic acid and its calcium, magnesium, sodium and ammonium salts, polyoxyethylene sorbitan monooleate with 20 oxirane groups, Resin acids, hydrogenated and dehydrogenated resin acids and their alkali metal salts, sodium dodecylated diphenyl ether disulfonate, and epoxy resins with a minimum content of 10% by weight of ethylene oxide Copolymer of ethane and propylene oxide. Preferably, the emulsifiers used are: sodium lauryl sulfate, sodium lauryl ether sulfate, ethoxylates (3 oxirane groups); polyethylene glycol (4-20) ether of oleyl alcohol and Polyethylene oxide (4-14) ether of nonylphenol. The biocide according to the invention may comprise here, for example, from 0.01% to 15% by weight, preferably from 0.02% to 8% by weight, particularly preferably from 0.05% to 6% by weight, and very particularly preferably by From 0.1% to 5% by weight emulsifier.

• Dispersants such as, for example, alkylphenol polyglycol ethers. The biocide according to the invention may comprise here, for example, from 0.01% to 15% by weight, preferably from 0.02% to 8% by weight, particularly preferably from 0.05% to 6% by weight, and very particularly preferably by From 0.1% to 5% by weight of dispersant.

• Stabilizers such as, for example, cellulose and cellulose derivatives. The biocide according to the invention may comprise here, for example, from 0.01% to 6% by weight, preferably from 0.01% to 3% by weight, particularly preferably from 0.01% to 2% by weight, and very particularly preferably by From 0.01% to 1% by weight stabilizer.

• Stabilizers, such as, for example, antioxidants, free radical scavengers or UV absorbers.

Binders or protective colloids, such as, for example, carboxymethylcellulose, natural and synthetic polymers in powder, granular or latex form, such as gum arabic, polyvinyl alcohol, polyvinyl acetate, and natural Phospholipids such as cephalins and lecithins, and synthetic phospholipids and paraffin oils. The biocide according to the invention may comprise here, for example, from 0.01% to 8% by weight, preferably from 0.05% to 4% by weight, particularly preferably from 0.2% to 3% by weight, and very particularly preferably by From 0.2% to 2% binder by weight.

• Spreading agents such as, for example, isopropyl myristate, polyoxyethylene nonylphenyl ether and polyoxyethylene laurylphenyl ether. The biocide according to the invention may comprise here, for example, from 0.01% to 20% by weight, preferably from 0.1% to 10% by weight, particularly preferably from 0.1% to 5% by weight, and very particularly preferably by From 0.1% to 2% by weight of spreading agent.

Fragrances and dyes, such as inorganic pigments such as iron oxide, titanium oxide, Prussian blue, and organic dyes such as alizarin, azo and metal phthalocyanine dyes and trace nutrients such as iron salts, manganese salts, boron salts, copper salts , cobalt salts, molybdenum salts and zinc salts. The biocides according to the invention may comprise here, for example, from 0.001% to 4% by weight, preferably from 0.01% to 1% by weight, particularly preferably from 0.01% to 0.8% by weight, of Spices and dyes.

• Buffer substances, buffer systems or pH regulators. The biocides according to the invention may comprise, for example, in each case from 0.01% to 10% by weight, preferably from 0.1% to 5% by weight, of buffer substances, buffer systems or pH regulators.

Thickeners such as, for example, polysaccharides, xanthan gum, sodium or magnesium silicate, heteropolysaccharides, alginates, carboxymethylcellulose, gum arabic or polyacrylic acid, preferably xanthan gum.

• Dedusting agents are eg polyethylene glycols and polyethylene glycol ethers. The biocides according to the invention can be contained here, for example, in each case from 0.01% to 2% by weight, preferably from 0.05% to 1% by weight, particularly preferably from 0.1% to 0.5% by weight.

• Leveling or release agents which can be used are, for example, highly dispersed silicon dioxide or magnesium salts of fatty acids. The biocide according to the invention can comprise here in each case from 0.01% to 5% by weight, preferably from 0.05% to 3% by weight, particularly preferably from 0.1% to 2% by weight Levelers are used to improve the flowability of solids.

• Packaging preservatives are eg biocides, bactericides and fungicides. The biocides according to the invention can comprise here, for example, from 0.01% to 2% by weight, preferably from 0.05% to 1% by weight, of packaging preservatives.

The total content of the aforementioned adjuvants in the biocide according to the invention is, for example, from 0.001% to 20% by weight, preferably from 0.1% to 15% by weight and particularly preferably from 0.1% to 10% by weight .

Solid formulations, like powder mixtures or water-dispersible granules (WG), for example, may contain solid auxiliaries in addition to these microencapsulated iodopropargyl compounds, like, for example, natural stone powders such as kaolin, Clay, talc, marble, chalk, quartz, attapulgite, montmorillonite or diatomaceous earth or synthetic inorganic substances such as highly dispersed silica, alumina and silicates, or mixtures thereof.

These solid formulations can be obtained in a manner known per se, for example by intimately mixing the microcapsules according to the invention with the solid auxiliaries, or by comminuting the combination of solid auxiliaries and the microencapsulated iodopropargyl compounds. Furthermore, these solid formulations can be obtained by drying (eg spray drying) liquid formulations.

Preferred solid formulations comprise, for example, from 10% to 99.999% by weight, preferably from 15% to 99.9% by weight, of microcapsules according to the invention.

Liquid formulations may be, for example, suspension concentrates, dispersions, gels or pastes.

Preferred liquid formulations are preferably aqueous dispersions.

The liquid formulations, such as in particular the dispersions, can be obtained, for example, by co-crushing the additional substances to be present in the liquid formulation and then adding the microencapsulated iodopropargyl compounds, or by incorporating the microencapsulated The iodopropargyl compound and the other substances to be present in the liquid formulation are mixed intimately with each other by means of a dissolver or stirrer in a manner known per se.

These liquid formulations generally comprise from 2 to 95% by weight, preferably from 5 to 75% by weight and very particularly preferably from 5 to 50% by weight of microcapsules according to the invention.

The present invention furthermore relates to the use of the microcapsules according to the invention or the biocide according to the invention for protecting industrial materials and industrial materials comprising the biocide according to the invention or the microcapsules according to the invention.

Industrial materials are, for example, building materials, wood, wood-based materials, wood-plastic composites, sealing compositions, joint seals, plastics, membranes, stone panels, textiles such as tarps and tents, textile composites, coating compositions Like, for example, paints, wall paints, wood protection paints, house facade paints, exterior paints, interior paints, emulsion paints, silicate paints, varnishes, concrete, cement, mortar or plaster, preferably silicate-bound, mineral , resin-bonded or silicone-resin-bound plasters, synthetic resin plasters, wood coatings, wood screeds, concrete coatings, roof tile coatings, sealing compositions or textile coatings.

As in the construction industry, the coating compositions according to the invention also find further applications in medical technology, the textile industry, the rubber industry, the sealant industry, the agricultural industry and laboratory technology.

An advantage of the invention is believed to be the excellent (ie reduced) leaching behavior of the microcapsules according to the invention. According to the invention, it is thus possible to use smaller quantitative amounts for the protective coating composition and to achieve significantly longer exposure times.

The following examples illustrate the invention.

example

Examples 1 to 4 describe the production of IPBC microcapsules.

The following materials are used here:

name

- Gum Arabic solution (4% by weight)

- Coadis ^™ BR3 (50% by weight in H ₂ O) (dispersant; aqueous solution of polyacrylate salt from Coatex)

- SRE (silicone defoamer emulsion defoamer from Wacker)

-Preventol MP 100 (IPBC)

- /water solution (1:1) (from INEOS Melamines MF 921w/85WA melamine-formaldehyde polymer)

- S25 (emulsifier based on tristearyl phenyl ether ethoxylate)

- BM 25 (packaging preservative containing 2.4% by weight benzisothiazolinone and 4.9% by weight methylisothiazolinone)

- (Xanthan gum based thickener from Solvay Rhodia)

- urea

The size of these microcapsules was determined by means of laser diffraction. Add solid capsules or suspensions/formulations therefrom. Use the following instruments and settings:

Instrument: with PIDS technology (polarization intensity differential scattering technique) from Bei

LS 13 from Beckmann Coulter

320 particle size analyzer

Sample Module: Universal Liquid Module (ULM)

Light source: Diffraction: solid state (780nm); PIDS: tungsten with bandpass filter

Filament lamps (450, 600 and 900nm)

Measurement time: 90 seconds, ultrasonic 15s before measurement

Calculation: Fraunhofer model

Result: Diameter D50% and D90% of volume distribution

Example 1

Production of IPBC-containing microcapsules (post-stirring time 4h at 70°C)

In a 1 L stainless steel tank, 3.76 g of Coadis BR, 37.5 g of a 4% strength by weight solution of gum arabic and 3.03 g of Wacker SRE defoamer were treated with stirring in 637.22 g of water at room temperature to give Slightly cloudy solution.

The pH was then lowered from pH=7.70 to pH=2.96 by adding 8.85 g of a 50% strength by weight solution of citric acid in water.

The solution thus obtained was transferred to a 1000 ml Planschlifftopf with impeller stirrer and Ultraturrax. Using an impeller stirrer, 150.09 g of IPBC was added at about 400-420 rpm.

The mixture was then heated to 70°C, during which time, above 60°C and as the IPBC started to melt, the Ultra-Turrax was turned on (15600rpm) and, after reaching 70°C, the mixture was emulsified for at least 30min .

Then, 150 g of a 50% strength by weight solution of Marprenal MF 921w/85WA in water were metered in over the course of 3 h. The Ultra-Turrax initially ran continuously. After 10% of the melamine-formaldehyde polymer had been metered in, the Ultra-Turrax was switched off and the reaction mixture was stirred using only the impeller stirrer at a constant stirring speed.

After complete metering of the melamine-formaldehyde polymer, the reaction mixture was post-stirred for a further 4 h at 70° C., then left to stand and filtered off with suction under membrane-pump vacuum. The wet cake was then washed with 67g, 27g and 7g of hot (80°C) water.

This gave 312.50 g of a white wet product.

The product from the beginning of application (T×T×t): 70°C×70°C×7h=34300(°C) ² h

Product after application (T×T×t): 70°C×70°C×4h=19600(°C) ² h

Particle size:

D50 [μm]: 29.9

D90 [μm]: 45.1

To measure the water and active ingredient content, a small sample was dried on a rotary evaporator for 2 h, and the IPBC content in the dried capsule mass was determined by means of IPBC.

IPBC content in dry mass: 69.5% by weight

Particle size:

D50 [μm]: 24.0

D90 [μm]: 37.6

The wet product (entry 1a) and the dried capsules (entry 1b) were investigated with regard to their active ingredient release in water in the leaching test. The results are given in Table 1 below.

Example 2

Production of microcapsules containing IPBC (post stirring time 4h at 85°C)

Microcapsules were produced analogously to Example 1, except that after complete metering of the melamine-formaldehyde polymer, the reaction mixture was post-stirred at 85° C. for a further 4 h.

This gave 312.50 g of a white wet product.

The product from the beginning of application (T×T×t): 70°C×70°C×3h+85°C×85°C×4h=43600(°C) ² h

The product (T×T×t) after application is completed: 85°C×85°C×4h=28900(°C) ² h

Particle size:

D50 [μm]: 22.3

D90 [μm]: 37.7

119.76 g of this wet product were dried on a rotary evaporator. This yielded 80.06 g of dry capsules as a white powder with an IPBC content of 67.1% by weight.

Particle size:

D50 [μm]: 19.7

D90 [μm]: 34.6

The wet product (entry 2a) and the dry capsules (entry 2b) were studied with regard to their active ingredient released in water in the leaching test. The results are given in Table 1 below.

Preparation of formulations from wet products

Stir 151.35 g of water with 0.76 g of completely molten Soprophor S/25 using a propeller stirrer at about 300 rpm, then add 84.22 g of wet product and use 0.25 g of 50% strength by weight NaOH solution from 4.0 Adjust pH to 8.1. Then, 12.43 g of urea was added, the mixture was stirred for 10 minutes until all had dissolved, and then 0.38 g of Rhodopol-G was slowly added with further stirring, and the mixture was stirred for 1 h until the formulation was homogeneous. The formulation was then preserved by adding 0.95 g of Preventol BM 25.

This yielded 250 g of a white formulation with an IPBC content of 16.0% by weight.

Particle size:

D50 [μm]: 21.8

D90 [μm]: 57.9

This formulation was investigated with regard to its active ingredient release in water in a leaching test (entry 2c). The results are given in Table 1 below.

Preparation of formulations from dry capsules

Stir 178.0 g of water with 0.76 g of completely molten Soprophor S/25 using a propeller stirrer at about 300 rpm, then add 55.88 g of these dry capsules and use 0.23 g of a 50% strength by weight NaOH solution to adjust pH to 8.3. Then, 12.49 g of urea were added, the mixture was stirred for 10 minutes until everything had dissolved, and then 0.40 g of Rhodopol-G was added slowly with further stirring, and stirring was carried out for 1 h until the formulation was homogeneous. The formulation was then preserved by adding 0.95 g of Preventol BM 25.

This yielded 250 g of a white formulation with an IPBC content of 13.6% by weight.

Particle size:

D50 [μm]: 20.4

D90 [μm]: 37.5

This formulation was investigated with regard to its active ingredient release in water in a leaching test (entry 2d). The results are given in Table 1 below.

Example 3

Production of microcapsules containing IPBC (post stirring time 18h at 80°C)

Microcapsules were produced analogously to Example 1, except that after complete metering of the melamine-formaldehyde polymer, the reaction mixture was post-stirred at 80° C. for a further 18 h.

This gave 253.98 g of a white wet product. The content of IPBC was 50.2% by weight.

The product from the beginning of application (T×T×t): 70°C×70°C×3h+85°C×85°C×18h=144750(°C) ² h

The product (T×T×t) after application is completed: 85°C×85°C×18h=130050(°C) ² h

Particle size:

D50 [μm]: 19.2

D90 [μm]: 39.4

123.95 g of this wet product were dried on a rotary evaporator. This yielded 91.92 g of dry capsules as a white powder with an IPBC content of 67.7% by weight.

Particle size:

D50 [μm]: 19.3

D90 [μm]: 33.7

The wet product (entry 3a) and the dried capsules (entry 3b) were investigated with regard to their active ingredient release in water in the leaching test. The results are given in Table 1 below.

Preparation of formulations from wet products

Use a propeller stirrer to stir 160 g of water with 0.76 g of completely molten Soprophor S/25 at about 300 rpm, then add 75.11 g of wet product and use 0.24 g of a 50% concentration by weight NaOH solution from 4.0 to 8.8 Adjust pH. Then, 12.52 g of urea was added, the mixture was stirred for 10 minutes until all had dissolved, and then 0.38 g of Rhodopol-G was slowly added with further stirring, and the mixture was stirred for 1 h until the formulation was homogeneous. The formulation was then preserved by adding 0.95 g of Preventol BM 25.

This yielded 250.3 g of a white formulation with an IPBC content of 14.7% by weight.

Particle size:

D50 [μm]: 21.4

D90 [μm]: 81.2

This formulation was investigated with regard to its active ingredient release in water in a leaching test (entry 3c). The results are given in Table 1 below.

Preparation of formulations from dry capsules

178.5 g of water was stirred with 0.80 g of fully molten Soprophor S/25 using a propeller stirrer at about 300 rpm, then 55.53 g of these dry capsules were added and the pH was adjusted to 8.3 using 0.95 g of 1M NaOH solution. Then, 12.49 g of urea was added, and the mixture was stirred for 10 minutes until everything had dissolved, and then 0.38 g of Rhodopol-G was slowly added with further stirring, and the mixture was stirred for 1 h until the formulation was homogeneous. The formulation was then preserved by adding 0.95 g of Preventol BM 25.

This yielded 250.2 g of a white formulation with an IPBC content of 15.8% by weight.

Particle size:

D50 [μm]: 20.4

D90 [μm]: 36.1

This formulation was investigated with regard to its active ingredient release in water in a leaching test (entry 3d). The results are given in Table 1 below.

Example 4

Production of IPBC-containing microcapsules (post-stirring time 22.5 h at 80 °C with sodium sulfate)

Microcapsules were produced analogously to Example 1, except that after the complete metering of the melamine-formaldehyde polymer at 80° C. the reaction mixture was stirred for a further 20 h and after the addition of 99.1 g of sodium sulfate the temperature was continued at 80° C. Another 2.5h.

Product from start of administration (T×T×t):

70℃×70℃×3h+85℃×85℃×22.5h＝177262.5(℃) ² h

The product after the application is completed (T×T×t): 85°C×85°C×22.5h=162562.5(°C) ² h

To produce wet product and formulation, the still hot mixture is separated.

Preparation of wet product

519.07 g of this mixture were released and filtered with suction under membrane-pump vacuum. The wet cake was then washed with 52g, 52g and 26g of hot (80°C) water. The mixture was then suction dried for an additional 15 minutes.

This gave 152.12 g of wet product.

Particle size:

D50 [μm]: 22.2

D90 [μm]: 78.9

To measure the water and active ingredient content, a small sample was dried on a rotary evaporator at 80° C. and 80 mbar for 2 h, and the IPBC content in the dried capsule mass was determined by means of IPBC.

IPBC content in dry mass: 68.4% by weight

Particle size:

D50 [μm]: 21.1

D90 [μm]: 61.9

The wet product (entry 4a) and the dried capsules (entry 4b) were studied with regard to their active ingredient released in water in the leaching test. The results are given in Table 1 below.

Preparation of formulations from reaction suspensions

435.80 g of the remaining suspension were mixed with 5.51 g of a 33% strength by weight solution of Soprophor S/25 in water with stirring. The pH was then adjusted from 4.03 to 8.40 using 1.38 g of a 40% strength by weight NaOH solution. Then, with further stirring, 21.79 g of urea and 2.46 g of Rhodopol G were added, and the mixture was stirred for another 2 h until homogeneous. This gave 466.95 g of a white suspension with an IPBC content (HPLC) of 12.1% by weight.

Particle size:

D50 [μm]: 20.3

D90 [μm]: 34.3

This formulation was investigated with regard to its active ingredient release in water in a leaching test (entry 4c). The results are given in Table 1 below.

Preparation of Formulations from Wet Cake

Stir 300.0 g of water with 1.43 g of completely molten Soprophor S/25 with a propeller stirrer at about 300 rpm, then add 143.36 g of the wet cake from Example 1a and use 0.7 g of 50% strength NaOH solution in order to 4.2 to 7.2 to adjust the pH. Then, 23.75 g of urea was added, and the mixture was stirred for 10 minutes until everything had dissolved, and then 0.71 g of Rhodopol-G was slowly added with further stirring, and the mixture was stirred for 2 h until the formulation was homogeneous. The formulation was then preserved by adding 0.95 g of Preventol BM 25 (a preservative of 2.4% benzisothiazolinone and 4.9% methylisothiazolinone).

This yielded 478.72 g of a white formulation with an IPBC content of 14.6%.

Particle size:

D50 [μm]: 19.4

D90 [μm]: 31.6

This formulation was investigated with regard to its active ingredient release in water in a leaching test (entry 4d). The results are given in Table 1 below.

Example 5 (comparative experiment from WO 2004000953 similar to Preparation Example 3)

In a 1 L stainless steel tank, 0.99 g of gum arabic, 4.99 g of Wacker SRE antifoam and 272.50 g of Preventol MP 400 (a 40% strength suspension of IPBC in water) were stirred into 394.9 g of water. The pH was then adjusted from 3.91 to 2.09 by adding 99 g of 12% strength by weight citric acid. The dispersion was heated to 60° C. and, with stirring, 217 g of a 50% strength by weight solution of Marprenal MF921w/85WA in water were metered in over the course of 1 h. The mixture was then post-stirred at 60 °C for 2 h.

144 g of the capsule dispersion were filtered and washed with 25 g and 20 g of cold water. This yielded 40.15 g of a wet cake with an IPBC content of 34.7% by weight.

4.67 g of this wet cake were dried on a rotary evaporator. This yielded 2.90 g of a white powder with an IPBC content of 55.9% by weight.

Product from start of application (T×T×t): 60°C×60°C×3h=10800(°C) ² h

The product after application (T×T×t): 60°C×60°C×2h=7200(°C) ² h

Both samples were investigated with regard to their leaching behavior (see Table 1).

Leaching test for microcapsules containing IPBC

In a 100 ml screw cap glass jar, the amount of the preparation containing 280 ppm of IPBC (based on 100 g) was weighed and filled up to 100 g with water. The screw top jar was closed and the sample was shaken on a circular shaker at 250 rpm and 20°C. After 24 hours (24h leaching test) and 72 hours (72h leaching test), 1 ml of sample was removed using a pipette and transferred to a reaction vessel. The sample was centrifuged at 14000 rpm for 6 minutes and the supernatant analyzed by means of high performance liquid chromatography.

Although the solubility of IPBC in pure water is 135 ppm, the solubility of IPBC in the test medium can be greater due to microcapsule or formulation components.

Table 1

Claims (15)

Claims 1. Microcapsules comprising at least one iodopropargyl compound, wherein the at least one iodopropargyl compound is microencapsulated with a microencapsulating material comprising at least one melamine-formaldehyde polymer. 2. Microcapsules according to claim 1, characterized in that they comprise 3-iodo-2-propynylbutylcarbamate. 3. Microcapsules according to claim 1 or 2, characterized in that the microcapsules have a volume average particle diameter of from 0.3 to 100 μm, preferably from 5 to 60 μm. 4. Microcapsules according to one of claims 1 to 3, characterized in that they have a D90 value determined by laser derivatization of 90 μm or less, preferably 60 μm or less, particularly preferably 10 to 60 μm . 5. Microcapsules according to one of claims 1 to 4, characterized in that they comprise at least one additional microencapsulating material selected from the group of synthetic, semi-synthetic or natural polymers. 6. Microcapsules according to any one of claims 1 to 5, characterized in that the weight ratio of the microencapsulated material to the at least one iodopropargyl compound is from 1:10 to 100:1, preferably Preferably from 1:10 to 10:1 and very particularly preferably from 1:4 to 2:1. 7. Microcapsules according to one of claims 1 to 6, characterized in that the microcapsules have from 1 to 80 parts per million (ppm), preferably from 2 to 50 ppm, particularly preferably from 5 to 40 ppm And very particularly preferred is a 24h leaching rate of 5 to 30 ppm, determined by means of a 24h leaching test. 8. A method for producing microcapsules according to one of claims 1 to 7, comprising at least: a) Applying a microencapsulated material comprising at least one melamine-formaldehyde polymer to at least one iodopropargyl compound b) during the period of t, at temperatures from 50°C to 95°C, preferably 64°C to 95°C, preferably 68°C to 95°C, particularly preferably 70°C to 95°C and very particularly preferably 70°C to 90°C °C at a temperature T such that the product T×T×t is >18000, preferably >20000 and particularly preferably >25000 (°C) ² h. 9. The method according to claim 8, characterized in that the application in a) is carried out in such a way that the aqueous emulsion or suspension of the at least one iodopropargyl compound is mixed with at least one melamine contacting the formaldehyde polymer and causing the application of the at least one melamine-formaldehyde polymer to the at least one iodopropargyl compound by reducing the solubility of the at least one melamine-formaldehyde polymer. 10. The method according to claim 9, characterized in that the reduction of solubility occurs by increasing the electrolyte content or by adjusting the pH. 11. The method according to one of claims 8 to 10, characterized in that the product TxTxt refers to the time period and temperature after the administration of the microencapsulated material has ended. 12. Biocide comprising microcapsules according to one of claims 1 to 7. 13. Use of the microcapsules according to one of claims 1 to 7 in or as a biocide. 14. Method for controlling microorganisms on industrial materials or for protecting industrial materials from changes in microorganisms or infestation by microorganisms, characterized in that the industrial materials are combined with microorganisms according to one of claims 1 to 7. The capsule or the biocide according to claim 12 is contacted or finished with it. 15. The method according to claim 14, characterized in that the industrial material is a construction material, wood, wood-based materials, wood/plastic composites, sealing compositions, plastics, films, stone slabs, textiles, textile composites or coatings combination.